Investigators want to question a person of interest about a pipe bomb and propane tanks found after a fire at a Littleton mall, a discovery that raised the possibility of a connection to the Columbine massacre anniversary.

Firefighters found two propane tanks and the bomb near the Southwest Plaza Mall’s food court after a small fire broke out Wednesday that was quickly squelched. The mall was evacuated around noon. No one was injured and the bombs didn’t explode.

Wednesday was the 12th anniversary of the shooting rampage at nearby Columbine High School and officials expressed concern that the mall incident could be somehow linked.